Philips TDA4686 free download

File name Tda4686.pdf

INTEGRATED CIRCUITS DATA SHEET TDA4686 Video processor with automatic cut-off control Preliminary specification File under Integrated Circuits, IC02 May 1993 Philips Semiconductors Preliminary specification Video processor with automatic cut-off control FEATURES · Intended for double line frequency application (100/120 Hz) · Operates from an 8 V DC supply · Black level clamping of the colour difference, luminance and RGB input signals with coupling-capacitor DC level storage · Two analog RGB inputs, selected either by fast switch signals or the I2C-bus; brightness and contrast control of these RGB inputs · Saturation, contrast, brightness and white adjustment via I2C-bus · Same RGB output black levels for Y/CD and RGB input signals · Timing pulse generation from either a 2- or 3-level sandcastle pulse for clamping, vertical synchronization and cut-off timing pulses · Automatic cut-off control or clamped output selectable via I2C-bus · Automatic cut-off control with picture tube leakage current compensation · Cut-off measurement pulses after end of the vertical blanking pulse or end of an extra vertical flyback pulse · Increased RGB signal bandwidths · Two switch-on delays to prevent discolouration before steady-state operation · Average beam current and peak drive limiting · PAL/SECAM or NTSC matrix selection via I2C-bus · Emitter-follower RGB output stages to drive the video output stages · I2C-bus controlled DC output e. g. for hue-adjust of NTSC (multistandard) decoders · No delay of clamping pulse · Large luminance, colour difference and RGB bandwidth GENERAL DESCRIPTION The TDA4686 is a monolithic, integrated circuit with a luminance and a colour difference interface for video processing in TV receivers. Its primary function is to process the luminance and colour difference signals from a colour decoder which is equipped e. g. with the TDA4686 multistandard decoder TDA4655 or TDA9160 plus delayline TD4661 and the Picture Signal Improvement (PSI) IC TDA467X or from a Feature Module. The required input signals are: · luminance and negative colour difference signals · 2- or 3-level sandcastle pulse for internal timing pulse generation · I2C-bus data and clock signals for microprocessor control. Two sets of analog RGB colour signals can also be inserted, e.g. one from a peritelevision connector and the other from an on-screen display generator. The TDA4686 has I2C-bus control of all parameters and functions with automatic cut-off control of the picture tube cathode currents. It provides RGB output signals for the video output stages. The TDA4686 is a simplified, pin compatible (except pin 18) version of the TDA4680. The module address via the I2C-bus can be used for both ICs; where a function is not included in the TDA4686 then the I2C-bus command is not executed. The differences with the TDA4680 are: · no automatic white level control; the white levels are determined directly by the I2C-bus data · RGB reference levels for automatic cut-o